112 GENERAL BOTANY 



cannot become uncoiled with any ordinary pull. The 

 rest of the tendril then twists round its axis so as to 

 form a spiral which brings the branch it belongs to, 

 nearer the support, and as the tissues harden becomes 

 a strong and elastic spring that yields when a branch 

 is swayed by the wind, and does not snap as a 

 straight connecting link would hardly fail to do. We 

 will refer again, more fully, to tendrils in chapter xiv. 



5. There are still other plants, which are not erect 

 and do not- climb, but grow more or less horizontally 

 along the surface of the ground. These for descriptive 

 purposes have been given special names. They are 

 -described as : 



decumbent when a short bit of the lower part of the 

 stem lies along the ground, while the greater part 

 rises upwards ; 



prostrate when the whole lies flat on the surface, 

 as in TRIBULUS TERRESTRIS (Nerinjee) and many 

 other small plants, and 



creeping when roots arise from the prostrate stems 

 and branches as in LIPPIA NODIFLORA (fig. 24). 



In sandy places, especially near the sea, creeping 

 plants are very common, and one of these IPOMCEA 

 BILOBA is characteristic of tropical seashores. Its 

 leaves are borne on stalks at intervals of six inches 

 or more along thin shoots which grow forward on the 

 surface, but are soon covered by the sand which is 

 driven by the wind along the beach. In this way they 

 become under-ground branches, and if they are all pulled 

 up, roots will be found growing down from the under 

 side of the nodes, and running deeply into the sand, 

 while the leaf-stalks may be short or long, but always 



